How to identify the quality of melt-blown non-woven fabric?
Melt-blown cloth is a high-speed hot air flow to draw a thin stream of polymer melt extruded from the die orifice, thereby forming ultra-fine fibers and collecting them on the condensed screen or roller, and at the same time bonding themselves to become Melt-blown non-woven fabric. Melt-blown fabric mainly uses polypropylene as the main raw material, and the fiber diameter can reach 1 to 5 microns.
The production process of melt-blown cloth is mainly as follows: melt preparation → filtration → metering → melt extrusion from the spinneret → melt fine flow drafting and cooling → web formation. Meltblown cloth weight: 18g-500g, width: generally 160cm and 180cm (can also be determined according to customer needs)
The melt-blown cloth has many voids, a fluffy structure, and good fold resistance. The ultra-fine fibers with unique capillary structure increase the number and surface area of fibers per unit area, so that the melt-blown cloth has good filterability, shielding, heat insulation and Oil absorption. It can be used in the fields of air, liquid filtration materials, insulation materials, absorption materials, mask materials, thermal insulation materials, oil-absorbing materials and wipers.
Meltblown cloth is the core material of masks. Medical masks and N95 masks are composed of spunbond layer, meltblown layer and spunbond layer. Among them, spunbond layer and meltblown layer are made of polypropylene PP material.
The protective mask needs to have at least three layers, both sides are spunbonded nonwoven fabrics, and the melt-blown nonwoven fabrics (that is, melt-blown fabrics) satisfying the weight in the middle. The inferior products of the two layers of the mask can be easily judged by observation, but the three layers are not that easy.
Simply put, a good meltblown fabric looks white rather than transparent due to its sufficient weight, and it has a clear difference from the spunbond nonwoven fabric on both sides (straightly speaking, it looks like paper, but fire It won't light, it will drop into black but there will be no flames burning). If the middle layer looks indistinguishable from both sides (uncommon), then it is not a meltblown cloth. If it looks different but is obviously thin, it is a melt-blown cloth with a small weight. The thinner the meltblown cloth, the worse the effect. The difference between medical (nursing) masks and medical surgical masks is here. And the same is a medical (nursing) mask, but also different in thickness.
Meltblown fabric is a type of nonwoven fabric, which is also called nonwoven fabric, so what are the characteristics of meltblown fabric?
Spunbond non-woven fabrics are not easy to tear and will not get into hands due to static electricity. Qualified melt-blown non-woven fabrics are obviously easy to tear, and will be stained by static electricity.
Spunbond non-woven fabrics and melt-blown non-woven fabrics are polypropylene products with little difference in combustion.
Use the melt-blown cloth that is close to white to be similar to the paper towel material, and use the classic effect to distinguish the spunbond non-woven cloth from the qualified melt-blown non-woven cloth.
The above are just some of our simple testing methods. Whether the melt-blown cloth really meets the requirements for mask use requires professional testing equipment to identify. General routine test items, particle over-rate efficiency test, bacterial over-rate efficiency tester, ventilation resistance test and other test items.